1979 ARRCO JOSE MARSHALL
- Thread starter JMP/HBE
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Lake Placid Blues
New member
Re: 1979 ARRCO JOSE MARSHALL
Most interesting. I watched the whole thing.
Comments:
Only one added tube gain stage. So much less gain than say the Soldano/5150/Rectifier type circuit. I was wondering why add an extra tube for just this, but then I saw he retained the jumped channels flexibility and the stock plexi clean signal path. The Marshall Vintage Modern design in HDR mode does all the same things with a much cleaner design from an engineering perspective, and without a diode clip.
The pull switch on the master volume allows the tone stack to be either pre the diode clip or post the diode clip. Very innovative.
He explained how the diode clip cleans up well with rolling the guitar volume down or backing off the pick attack which is big plus compared to most amps with a lot of preamp distortion. The Marshall Vintage Modern does this feature well. The Jubilee does but not as well as the VM but it has the luxury of a clean channel.
I was surprised that the diode clip is set up for symmetrical clipping. The Marshall Jubilee design provides an asymmetrical clip, as does the extra preamp tubes in other designs such the Soldano/5150/Rectifier and the Marshall DSL...ect..
All in all most educational. This is not the only Jose mod design as I understand the history, but one among many.
Most interesting. I watched the whole thing.
Comments:
Only one added tube gain stage. So much less gain than say the Soldano/5150/Rectifier type circuit. I was wondering why add an extra tube for just this, but then I saw he retained the jumped channels flexibility and the stock plexi clean signal path. The Marshall Vintage Modern design in HDR mode does all the same things with a much cleaner design from an engineering perspective, and without a diode clip.
The pull switch on the master volume allows the tone stack to be either pre the diode clip or post the diode clip. Very innovative.
He explained how the diode clip cleans up well with rolling the guitar volume down or backing off the pick attack which is big plus compared to most amps with a lot of preamp distortion. The Marshall Vintage Modern does this feature well. The Jubilee does but not as well as the VM but it has the luxury of a clean channel.
I was surprised that the diode clip is set up for symmetrical clipping. The Marshall Jubilee design provides an asymmetrical clip, as does the extra preamp tubes in other designs such the Soldano/5150/Rectifier and the Marshall DSL...ect..
All in all most educational. This is not the only Jose mod design as I understand the history, but one among many.
Lake Placid Blues
New member
Lake Placid Blues
New member
Re: 1979 ARRCO JOSE MARSHALL
LOL, What I was referring to was that the Vintage Modern in HDR had the extra tube gain stages in the preamp but still retained the jumped channel flexibility, and the stock signal paths in LDR, of a four holer.
I think Marshall made a mistake by using a post PI master volume in the VM. With a post PI master you mostly lose the functions of the negative feedback, until the amp is cranked up real loud.
LOL, What I was referring to was that the Vintage Modern in HDR had the extra tube gain stages in the preamp but still retained the jumped channel flexibility, and the stock signal paths in LDR, of a four holer.
I think Marshall made a mistake by using a post PI master volume in the VM. With a post PI master you mostly lose the functions of the negative feedback, until the amp is cranked up real loud.
JMP/HBE
Well-known member
Re: 1979 ARRCO JOSE MARSHALL
There are about a dozen other differences as well.
JMP/HBE
Well-known member
Lake Placid Blues
New member
Re: 1979 ARRCO JOSE MARSHALL
Well there are a few, but the biggest difference is the diode clip.
Well there are a few, but the biggest difference is the diode clip.
devastone
Well-known member
Re: 1979 ARRCO JOSE MARSHALL
OMG, it uses diodes for clipping!?!?!? It sounds like crap!
j/k, echoing what the sentiment for the JCM900s and other amps with diode clipping when they came out. FWIW, I did use one of the early 900s and it sounded great.
OMG, it uses diodes for clipping!?!?!? It sounds like crap!
j/k, echoing what the sentiment for the JCM900s and other amps with diode clipping when they came out. FWIW, I did use one of the early 900s and it sounded great.
Lake Placid Blues
New member
Re: 1979 ARRCO JOSE MARSHALL
Yeah I'm not pointing out the diode clip to denigrate the Jose amp, but that it is one reason the Jose sounds as does. And it sounds great. The diode clip design in the Jose provides a very good emulation of full power tube clipping including the dynamics at less than insane volume levels. It is a hard clip, but full power tube distortion is usually hard clip.
I found this commentary online by an engineer about emulating the properties of tube amps:
Yeah I'm not pointing out the diode clip to denigrate the Jose amp, but that it is one reason the Jose sounds as does. And it sounds great. The diode clip design in the Jose provides a very good emulation of full power tube clipping including the dynamics at less than insane volume levels. It is a hard clip, but full power tube distortion is usually hard clip.
I found this commentary online by an engineer about emulating the properties of tube amps:
devastone
Well-known member
Re: 1979 ARRCO JOSE MARSHALL
I didn't take it as a bad thing, just interesting that some of the same people that praise the Jose mods are some of the same people that scoffed at the diode clipping in the JCM900s. FWIW, I had a 50W SL-X and a High Gain Dual Reverb heads and really liked both of them. And yes, I realize the Jubilees had diode clipping as well, the first Marshalls to use it IIRC, but I guess they were acceptable since Slash used them.
I didn't take it as a bad thing, just interesting that some of the same people that praise the Jose mods are some of the same people that scoffed at the diode clipping in the JCM900s. FWIW, I had a 50W SL-X and a High Gain Dual Reverb heads and really liked both of them. And yes, I realize the Jubilees had diode clipping as well, the first Marshalls to use it IIRC, but I guess they were acceptable since Slash used them.
Cynical
Active member
Re: 1979 ARRCO JOSE MARSHALL
The problem with JCM900s isn't that they had diode clipping; the problem is, they sounded much worse than the JCM 800 2203/2204.
(In fairness, the same was also true of the Silver Jubilee and 2210. And is also true of most "modded Marshall"-style amps I've encountered that aren't in the SLO/5150/Recto school.)
The problem with JCM900s isn't that they had diode clipping; the problem is, they sounded much worse than the JCM 800 2203/2204.
(In fairness, the same was also true of the Silver Jubilee and 2210. And is also true of most "modded Marshall"-style amps I've encountered that aren't in the SLO/5150/Recto school.)
Gtrjunior
New member
Re: 1979 ARRCO JOSE MARSHALL
I believe you’re right. There were 3 900 versions. The SL-X was all tube and the other 2 used diodes
I believe you’re right. There were 3 900 versions. The SL-X was all tube and the other 2 used diodes
devastone
Well-known member
Re: 1979 ARRCO JOSE MARSHALL
I think you are right, that was at least a decade and a half ago... Just looked up the schematic and the SL-X didn't use diodes, but it did have a TL072 opamp in the circuit. Really good sounding amps IMHO, of course, YMMV. I really liked the HGDR version with the clean channel too, which did use diodes. Tons of artists used them when they came out, John 5 still uses one.
I think you are right, that was at least a decade and a half ago... Just looked up the schematic and the SL-X didn't use diodes, but it did have a TL072 opamp in the circuit. Really good sounding amps IMHO, of course, YMMV. I really liked the HGDR version with the clean channel too, which did use diodes. Tons of artists used them when they came out, John 5 still uses one.
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